Petrus: There are many things about this tractor that I like; for instance, the fact that it is a 125 which I think is one very tough tractor (and which some people feel represents the apex [highest point] of Cub Cadet development), the steering wheel looks fantastic (I wish I had one like that, so neat!), the shift lever also appears to be in very good condition (better than the one on my 149!), in short, everything (or most everything) is there for a very good price.
The things I see which concern me are, (1) the +/- 60 Amp gauge instead of the stock +/- 15 (or +/- 30, I can't remember) --it definitely isn't original, but you shouldn't have an issue replacing it with an IH version; (2) what the owner reports about the engine.
Despite the fact that it doesn't look like it has been recently rebuilt, I would not discount the owner's story --what else do you have to go on? I also take note of the fact that the tractor is obviously not running, everything operational has been disconnected and is "laying there" including the starter generator.
I would approach the whole project as an "unknown" and proceed accordingly. Take everything apart, examine, and reassemble. If there is something wrong in the engine, check and verify. Follow the manual. Disassemble, measure everything, reassemble per service manual, fix everything you find along the way.
Be assured: The tractor is worth effort. A Model 125, properly done, would be the envy of many.
Good Luck.
However, if you get to looking at it, and it is not something you want to get into, I imagine there are those who wouldn't mind taking it off your hands --for a profit!